import { useState, useMemo } from "react";
import { useTranslation } from "react-i18next";
import { Tag } from "lucide-react";
import type { RecentTransaction } from "../../shared/types";
import ContextMenu from "../shared/ContextMenu";

export interface CategoryTransactionsTableProps {
  transactions: RecentTransaction[];
  onAddKeyword?: (transaction: RecentTransaction) => void;
}

type SortKey = "date" | "description" | "amount";

function formatAmount(amount: number, language: string): string {
  return new Intl.NumberFormat(language === "fr" ? "fr-CA" : "en-CA", {
    style: "currency",
    currency: "CAD",
  }).format(amount);
}

export default function CategoryTransactionsTable({
  transactions,
  onAddKeyword,
}: CategoryTransactionsTableProps) {
  const { t, i18n } = useTranslation();
  const [sortKey, setSortKey] = useState<SortKey>("amount");
  const [sortDir, setSortDir] = useState<"asc" | "desc">("desc");
  const [menu, setMenu] = useState<{ x: number; y: number; tx: RecentTransaction } | null>(null);

  const sorted = useMemo(() => {
    const copy = [...transactions];
    copy.sort((a, b) => {
      let cmp = 0;
      switch (sortKey) {
        case "date":
          cmp = a.date.localeCompare(b.date);
          break;
        case "description":
          cmp = a.description.localeCompare(b.description);
          break;
        case "amount":
          cmp = Math.abs(a.amount) - Math.abs(b.amount);
          break;
      }
      return sortDir === "asc" ? cmp : -cmp;
    });
    return copy;
  }, [transactions, sortKey, sortDir]);

  function toggleSort(key: SortKey) {
    if (sortKey === key) setSortDir((d) => (d === "asc" ? "desc" : "asc"));
    else {
      setSortKey(key);
      setSortDir("desc");
    }
  }

  const handleContextMenu = (e: React.MouseEvent, tx: RecentTransaction) => {
    if (!onAddKeyword) return;
    e.preventDefault();
    setMenu({ x: e.clientX, y: e.clientY, tx });
  };

  const header = (key: SortKey, label: string, align: "left" | "right") => (
    <th
      onClick={() => toggleSort(key)}
      className={`${align === "right" ? "text-right" : "text-left"} px-3 py-2 font-medium text-[var(--muted-foreground)] cursor-pointer hover:text-[var(--foreground)] select-none`}
    >
      {label}
      {sortKey === key && <span className="ml-1">{sortDir === "asc" ? "▲" : "▼"}</span>}
    </th>
  );

  return (
    <div className="bg-[var(--card)] border border-[var(--border)] rounded-xl overflow-hidden">
      <div className="overflow-x-auto max-h-[500px] overflow-y-auto">
        <table className="w-full text-sm">
          <thead className="sticky top-0 z-10 bg-[var(--card)]">
            <tr className="border-b border-[var(--border)]">
              {header("date", t("transactions.date"), "left")}
              {header("description", t("transactions.description"), "left")}
              {header("amount", t("transactions.amount"), "right")}
            </tr>
          </thead>
          <tbody>
            {sorted.length === 0 ? (
              <tr>
                <td colSpan={3} className="px-3 py-4 text-center text-[var(--muted-foreground)] italic">
                  {t("reports.empty.noData")}
                </td>
              </tr>
            ) : (
              sorted.map((tx) => (
                <tr
                  key={tx.id}
                  onContextMenu={(e) => handleContextMenu(e, tx)}
                  className="border-b border-[var(--border)] last:border-0 hover:bg-[var(--muted)]/40"
                >
                  <td className="px-3 py-2 tabular-nums text-[var(--muted-foreground)]">{tx.date}</td>
                  <td className="px-3 py-2 truncate max-w-[280px]">{tx.description}</td>
                  <td
                    className="px-3 py-2 text-right tabular-nums font-medium"
                    style={{
                      color: tx.amount >= 0 ? "var(--positive, #10b981)" : "var(--foreground)",
                    }}
                  >
                    {formatAmount(tx.amount, i18n.language)}
                  </td>
                </tr>
              ))
            )}
          </tbody>
        </table>
      </div>

      {menu && onAddKeyword && (
        <ContextMenu
          x={menu.x}
          y={menu.y}
          header={menu.tx.description}
          onClose={() => setMenu(null)}
          items={[
            {
              icon: <Tag size={14} />,
              label: t("reports.keyword.addFromTransaction"),
              onClick: () => {
                onAddKeyword(menu.tx);
              },
            },
          ]}
        />
      )}
    </div>
  );
}